The space elevator will be built about 50 years after everyone stops laughing.

In the long run, there are no secrets. in science. The universe will not cooperate in a cover-up.

Astronomy, as nothing else can do, teaches men humility.

Moses Kaldor had always loved mountains; they made him feel nearer to the God whose nonexistence he still sometimes resented.

As three laws were good enough for Newton, I have modestly decided to stop there.

At the present rate of progress, it is almost impossible to imagine any technical feat that cannot be achieved - if it can be achieved at all - within the next few hundred years.

I'm quite fond of the writer who told a beginning author, "If you've got a message, use Western Union."